rome and the dramatic scene at the vatican today. Pope benedict making his first appearance since his resignation announcement. There was a kind of rumbling in rome, a kind of aftershock and abc's dan harris is at the vatican to tell us more. Reporter: On this ash wednesday, at his last public mass, pope benedict received a rare, rapture rouse standing ovation. Earlier in the day, at a public say mowny, a similar reception, with cheers and tears. Benedict was visibly moved. How was the atmosphere in the room? Electric. Solemn and electric at the same time. I almost cried. Honestly, it was wonderful. Reporter: Debeneath the applause, there are thorny questions swirling. We were struck by the fact that the pope said again today that he was resigning of his own free will. There's been a real emphasis on pointing out that the pope made this decision of his own volition. Why? Why is that? Because italians love conspiracy theories. Reporter: He's not kidding. The local papers here read like a dan brown novel, teaching with benedict being driven out by internal intrigue. Conservatives in the vatican are calling the pope's resignation a disaster, because it diminishes the job of god's infallible representative on earth. Can you actually give your two weeks notice? It's not a problem that the pope is renouncing the authority that he enjoys. He enjoys it only in as much as he's in office. Not as a personal thing. Reporter: In other words, as OF 8:00 P.M. ON FEBRUARY 28th, He will no longer be considered infallible. In that moment of resignation, there will be other dicate symbolic issues. What will the ex-pope's title be? What kind of robes will he wear? For centuries, when a pope deals, they seal his apartment to protect his documents and then ritually crush his papal ring with a small silver hammer. But today, the vatican admitted they still really don't know exactly how and when they will handle these ancient traditions in this highly unusual case. So, what we're watching here, diane, is a 2,000-year-old church entering genuinely uncharted waters.

This transcript has been automatically generated and may not be 100% accurate.

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